1. Field of the Invention
The present invention relates to a method of handling photographic film and a film cassette for containing the same, and more particularly to a photographic film handling method in which a cassette shell for containing unexposed film is reused.
2. Background
135 mm photographic film has been widely used in recent years in both compact cameras and single-use cameras. Therefore, the consumption of film contained in film cassettes is progressively increasing. The negative photofinishing process consists of a film developing process, a printing process and a paper developing process. There are simplified photofinishing systems including mini-laboratory equipment capable of continuously effecting the series of processes for the purpose of simple and rapid film developing operations. Additionally, there has been proposed a film cassette in which rotation of a spool in a direction of unwinding the photographic film causes a film leader to be fed outside the cassette shell, as described in U.S. Pat. Nos. 4,832,275, 4,834,306, and 4,846,418, Japanese Patent Laid-open Publication No. 2-124564, and a number of Japanese patent applications filed by the present applicant.
When a laboratory receives an order from a customer for processing a photographic film after exposure, an exposed film is drawn out of a cassette shell, developed, cut into film sheets of a predetermined length (e.g. of six image frames), inserted in a film sheath, and returned to the customer together with photoprints printed from the developed film. However, it is inconvenient to store and handle the cut film sheets because they require a relatively large space. This procedure is also inefficient because a posterior process is necessary to insert the film sheets in the film sheath after the film has been cut into the shorter film pieces. Further, reprinting of developed film cannot be performed efficiently because separated film pieces are spliced together in elongation therefor.
Conventionally, a photofinisher unwinds and separates an exposed film from the cassette shell for developing and printing, and throws the emptied cassette shells away. A great number of emptied cassette shells have been thrown away as industrial waste, which is undesirable in view of economy of resources and protection of the environment.